Many large corporations rely on a wide variety of different and often disparate computer systems that were implemented at various times and circumstances. The multiplicity of systems adds dramatically to a company's costs. Multiplicity also reduces efficiency and a company's operational economies of scale. Also, employees require extensive training in order to be able to use each of the different systems. The cost and inconvenience of upgrading all of these components into one easy to use computer system is also enormous.
Even if a company does manage to upgrade and merge all of its operations into a single computer system, when it wants to collaborate, merge, participate in joint ventures, at least some of the above-noted problems will arise. But, many companies do not upgrade applications because of the expense involved. Thus, there are many systems still in operation that require integration, but are very difficult to integrate, such as, systems that are only terminal-accessible.
Terminal-accessible systems, such as, one that requires access via a 3270 terminal, were the predominant applications architecture prior to the proliferation of personal computers (“PC”). Unlike PCs, such terminals were not capable of running software independently of a mainframe. While use of PCs has become widespread, there are still terminals in operation, as well as many terminal-accessible systems. In many places, PCs running software called 3270 emulation connect remotely to a computer running 3270 applications. This allows a PC to connect to a terminal-accessible system through an interface that functions like a terminal.
SQL (Structured Query Language) is a standard programming language adopted by the American National Standards Institute and the International Organization for Standardization for getting information from and updating a database. Many databases, such as, Access databases, support SQL queries.
As a result of the continued use of old systems, companies have begun integrating and automating computer systems. Integration, however is not an easy task to accomplish. To integrate many different systems into one user-friendly graphical user interface (“GUI”), a program must in some way control another program or access its data directly. So, for example, while arranging a purchase, a salesman may need to: (1) access a Legacy database to verify that a product is in stock and update inventory, (2) access a separate database to update the customer's information and (3) access a separate a website and affiliated database to arrange for shipping. Accessing each of these systems is both time consuming and redundant. The salesman would have to enter the product and customer information three different times each time he/she placed an order. In addition, the salesman would have to be familiar with how to navigate each of these systems.
By integrating all of these systems into one GUI, the salesman would only have to learn one system. Moreover, that employee could be trained quicker, and would not have to re-enter the same information more than once. The difficulty would arise in designing a GUI that can navigate all three of the above-exemplified systems. As previously noted, an interface would have to be designed for each system. While one standard interface could be used for the shipping website, such as a FedEx or UPS website, each Legacy and Access database is designed specifically for the company using it. Each company has unique information that it stores in its databases about products and customers. Accordingly, for each company the arduous task of designing software to interface with its various databases must be undertaken.
There are a three distinct techniques for one computer application to talk to another computer application—through the data layer, business logic layer or presentation layer. System A's business logic layer 52 must communicate with system B's data layer 58, business logic layer 57 or presentation layer 56 to access system B 55. Access through the data layer 58 allows direct modification of the data in system B's 55 database. Unfortunately, it is extremely time consuming, expensive and error-prone to interface directly with a system's data layer. As a result, many systems do not allow any direct manipulation or access to the data.
The second method for one system to communicate with a second system is though the second system's business logic layer. For system A 50 to access system B 55 through system B's business logic layer, a transaction interface needs to be developed for system B 55. As is the problem with accessing another system through the data layer, developing a transaction interface to access a system though its business logic layer is time consuming and expensive.
The third method for one system to communicate with a second system is through the second system's presentation layer. While not nearly as expensive as creating a transaction interface to access the business logic layer or accessing the data directly, interfacing with the presentation layer has problems. A particular problem is that the integrating application must wait an appropriate length of time after entering commands to insure that the program has moved to a new state after the commands were entered. However, the time that a state change takes is erratic, so this is problematic.
Another problem is the unpredictable nature of applications in general. When an application does not go to the expected state after a command is entered, a scripted agent is unable to recover without specific instructions being written to cover that situation. This is difficult because there is a near infinite number of ways that an application can behave.
One solution to the state change problem is to program the integrating application to determine which screen it is on. If the application being controlled used screens with unique identifiers, then screen identification information is accessible. If a screen has a unique identifier, the integrating application merely has to look at the unique identifier to know what screen it is on. Only about 20% or less of Legacy systems have applications that use screens with unique identifiers, so it is not an overall solution.
Another solution to the screen recognition issue is for the programmer to select regions of the screen for the software to examine in order to determine which screen is active. However, when a host system or application has numerous different screens it can be a time consuming and error-prone task for a programmer to determine which regions will work efficiently or work at all.
A programmer also has to determine how each screen is reached and from which screens it can be reached. This requires mapping the host application. To map the host application, a list of screens is created in the order they appear during navigation. Each entry in the list includes screen identification information. Necessary information (by using, for example, key words) include: (i) the action that takes place on that screen, (ii) attention identifier keys used on that screen, (iii) the next screen to be displayed, and (iv) the time it takes to navigate from one screen to the next screen.
The next step is to create an itemized description for each screen. This description includes the type of field (read-only, button, etc.), the possible values this field could hold and the appropriate response for each possible value, whether the field can be written to, what can be written to it, the location on the screen of the field, and the length of the field for each field in each screen.
Once this information is compiled, a directed graph or state diagram is created to illustrate the operation of the system. From the directed graph or state diagram, the code to interface with a system can be written. This must be repeated for each system that is to be integrated.
As can be seen from above, even under the best circumstances, the task of integrating disparate databases and computer software is complex, time consuming and expensive. Therefore, there exists a need in the art for software to simplify the process of modeling various systems and seamlessly integrating information access over extended networks.